Compared with blanket dry cow therapy (DCT), the selective antimicrobial treatment of cows based upon on-farm culture results has the potential to reduce the amount of antimicrobials used in dairy production. The objective of the current study was to determine the effect of a Petrifilm (3M Canada, L...

Control of sea lice in Chile is largely based on antiparasitic treatments, synthetic pyrethroids being the most used drugs. In recent years, farmers in Chile have reported decreased performance of pyrethroid-based treatments. The aim of this study was to assess the performance of two deltamethrin-ba...

A cross-classified and multiple membership Cox model was applied to calf mortality data from Western Canada, where 23,409 calves from 174 herds were followed for up to 180 days after calving. The herds were cross-classified by 49 veterinary clinics and 9 ecological regions and in a multiple membersh...

In Eastern Canada, an increasing number of pests, predators and pathogens in downriver areas (close to the ocean) have led the aquaculture industry to consider growing oysters in upriver areas (close to the river source). In this study, oyster growth performance was compared between downriver and up...

Mastitis is a complex disease affecting dairy cows and is considered to be the most costly disease of dairy herds. The hazard of mastitis is a function of many factors, both managerial and environmental, making its control a difficult issue to milk producers. Observational studies of clinical mastit...

Objectives:
The aim was to characterize the behaviour and faecal glucocorticoid metabolite (FGM) responses of six cats (Felis catus) to single caging for 30 days.
Design In this observational study, changes in outcome measures were monitored with habituation to caging. Continuous focal observat...

It is well documented that nursing is concerned about the social support needs of older adults and the effects of those needs on health and well-being. Using survey data from the Atlantic Seniors Housing Research Alliance, the authors explore the emotional and informational social support needs of c...

The decline of fisheries over recent decades and a growing human population has coincided with an increase in aquaculture production. As farmed fish densities increase, so have their rates of infectious diseases, as predicted by the theory of density-dependent disease transmission. One of the pathog...

This paper discusses statistical modelling for data with a hierarchical structure, and distinguishes in this context between three different meanings of the term hierarchical model: to account for clustering, to investigate variability and separate predictive equations at different hierarchical leve...

Gastrointestinal nematodes, such as Ostertagia ostertagi and several species of Cooperia, are ubiquitous in temperate climates and have been shown to have detrimental effects on production in adult dairy cattle. A published meta-analysis demonstrated that overall, producers lose approximately 0.35 k...

Freedom from infection modeling, using scenario trees, has become an established methodology and is well described in the literature. However, standards for organizing and reporting the surveillance information incorporated into such models are less developed.
Canada has been routinely testing for T...

In many veterinary studies, including clinical trials and epidemiological investigations, data are clustered into groups such as herds. When such data are analyzed, it has become more and more popular to look for possible heterogeneity in outcome between herds. However, beyond the investigation of s...

"This book started life as a veterinary text: Veterinary Epidemiologic Research. ... Methods in Epidemiologic Research is based heavily on the material covered in Veterinary Epidemiologic Research, with 2 major changes. Firstly, all of the veterinary examples have been replaced with human medic...

During the course of a multi-site clinical field trial comparing the field effectiveness of Atlantic salmon (Salmo salar L.) vaccines, an opportunity arose to examine the potential effects of repeated fish handling on the controlled trial outcome. Fish-level data obtained by seining, dip-netting and...

In Denmark, several political initiatives have been taken to reduce use of pesticides and fertilizer in order to avoid unwanted side effect of the increasing cropping intensification. Based on two nation wide surveys we investigate flora changes and discuss the changes in relation to biodiversity, c...

Conventional studies on the precision of diagnostic tests with binary outcomes report single descriptive estimates of agreement for a particular pool of samples. However, agreement for binary tests is intrinsically associated with the assay operating characteristics that are influenced by population...

In the absence of a reference standard, a latent class model (LCM) was used in this study to assess diagnostic sensitivity (DSe) and specificity (DSp) of a recently developed reverse-transcription polymerase chain reaction (RT-PCR) for infectious salmon anaemia virus (ISAV). The study included 4 pop...

An observational study was conducted in 63 Canadian dairy farms to evaluate the association of bulk tank milk selenium (Se) concentration (BTSe) with average daily milk yield, milk fat and milk protein, bulk tank somatic cell count (BTSCC), and the probability of being a Staphylococcus aureus-positi...

The Newfoundland and Labrador (NL) aquaculture industry is a major contributor of
salmon products that help meet protein needs for the world’s growing population. The industry
in NL continues to grow and evolve and now includes emerging species in its production such as
Atlantic cod. In a growing ...